Improvement in furnaces of bakers  ovens



r A. GRUMB-HE & B. DONAL-D.

Furnace of Baker's Ovens THE GRAPHIC CO.PHDTO-LITH.39&4I PARK PLAGLNJCALEXANDER ORUMBIE, OF NYAOK, AND DAVID DONALD, OF BROOKLYN, NEW YORK.

IMPROVEMENT IN FURNACES OF BAKERS OVENS.

Specification forming part of Letters Patent No. 161,489, dated March30, 1875; application filed March To all whom it may concern Be it knownthat we, ALEXANDER ORUM- BIE, of Nyack, in the county of Rockland andState of New York, and DAVID DONALD, of Brooklyn, in the county of Kingsand State of New York, have invented a new and useful Improvement inFurnaces of Bakers Ovens, applicable also to other purposes; and we dohereby declare that the following is a full, clear, and exactdescription of the same, reference being had to the accompanying drawingwhich forms part of this specification.

This invention, while applicable, amon g other purposes, to kilns, ismore especially designed to be applied to bakers ovens, and will here bedescribed more particularly with reference to such use. 7

Applied to bakers ovens the invention possesses all the advantages ofbaking by direct heat from an open fire, while the combustion of smokeis rendered perfect, and the dust prevented from rising into the oven.

The invention consists in a combination with one or more air chambers orspace having inlets for the supply of fresh air thereto,

and the fire-chamber of the furnace by which,

in connection with passages therefrom, said air-chambers are heated, ofa shield or cover to the furnace, whereby the gaseous products ofcombustion are made not only to impinge upon said shield and the oven isheated by radiation from the latter, but the heated air escaping fromthe air-chambers is made to mingle with the gaseous products ofcombustion as the latter pass from the fire-place under the shield, andthe smoke and other inflammable gases thereby consumed, and the wholeheat made to pass into the oven free from smoke and dust.

In the accompanying drawing, Figure 1 is a semi-sectional plan of theimproved furnace; Fig. 2, a vertical section on the line m0, and Fig. 3a further vertical section on the line y y.

A is the fire-place of the furnace, which is open above, and b 1)branches therefrom in communication with an outside space, E, of ahollow outer wall, within which the gases from the fire-place are atliberty to collect or cirand the fire-place A is an air-heating chamber,0, formed by an inner hollow wall inclosing the fire-place. Thisair-heating chamber 0 is supplied with air from the exterior by inlets cc, and said air, after being thoroughly heated, is free to pass outthrough apertures cl in the top of the furnace, which top is left openat e for direct escape of the gaseous products of combustion from thefire-place. Mounted on the top of the furnace, by any number ofinterposed piers ff, is a shield or cover, D, which may be made of anynumber of slabs, and of an area equal to the top of the furnace, orthereabout. This shield or cover, which is only slightly raised abovethe top of the furnace and its opening 0, becomes highly heated, in partby the direct action of the fire and in part by the combustion of theescaping gases therefrom, as affected by the comrningling with saidgases of the heated air from the chamber O, all the heated and inflamedgases passing up round the edges of the shield D into the oven. In thisway, or by these means, all the advantage which is to be derived bydirect heat from an open fire is obtained, together with a betterdistribution of the bottom heat by reason of the shield D, while thecombustion of the smoke and other combustible escaping gases is renderedper- -fect, and the dust prevented from rising, thus contributinglargely to the cleanliness as well as the economy of the oven.

Applied to a mechanical oven in which a reel, provided with pendentbread or other holders, is used, this improvement will be found ofspecial advantage.

I claim The combination, with the fire-place A, open above, asdescribed, and the outside heated space B, connected therewith, of theinterposed hot air-chamber O, and the shield or cover D, substantiallyas shown and described.

ALEXANDER ORUMBIE. DAVID DONALD.

Witnesses BENJAMIN W. HOFFMAN,

culate. Between this space or chamber B FRED HAYNEs.

